Starter.



D. T. BROWNLEE.

STARTER.

APPLICATION FILED FEB. 15, 1911.

1 ,263,642. Patented Apr. 23, 1918,

WITNESSES. IIVVENTOR Balm 6L!'I' Bkourn lee,

of the starting 4 UNI ED STATES PATENT OFFICE.

. DALMAR T. IBItOWNLEE, INDIANAPOLIS, INDIANA, ASSIGNOR 0F FOUR-FIF'IHSTO DAVID SPACKE, 0F INDIANAPGLIS, INDIANA.

STARTER.

Specification of Letters Patent.

Patented Apr. 23, 1918.

Application filed February 15, 1917. Serial No. 148,888.

To all whom it may concern:

Be it known that I, DALMAR T. BROWNLEE, a citizen of the United States,residing at Indianapolis, in the county of Marion and State of Indiana,have invented a new and useful Starter, of which the following is aspecification.

The object of my invention is to produce an improved form of startingmechanism, by means of which a motor, such as an internal combustionengine, may be set into motion by a small electric motor, theconstruction being-such that the connection between the startin motorand main motor may be automaticaily established and disestablished.

The accompanying drawings illustrate my invention.

Figure 1 is a side elevation of one form ofthe connecting gearing, indissociated position, with fragmentary adjacent portions motor andstarted motor; Fig. 2 is a similar view of another form of my invention;and Fig. 3 a diagrammatic view of the starting motor and the controllingswitch.

In the drawings, 10 indicates the starting moto having armature 11,field 12, field coils 13, in which battery 14 is in circuit, and a shortcircuiting resistance circuit 15 connected to the armature. Theresistance circuit 15 at one end terminates in a terminal 16 and thebattery circuit terminates at one end in a terminal 17 Arranged tocoiiperate with one or the other of these terminals 16 and 17 is aswitch 18 which is connected by wire 19 to the armature circuit. Aspring 21 serves to normally'keep switch 18 in contact with terminal 16,thus short-circuiting the armature through the resistance circuit 15,

and a pedal 22 is carried by switch 18 so that the switch 18 may beswung from terminal 16 to terminal 17 The starting motor 10 is providedwith a shaft 24 upon which is splined a spiral gear 25 which is backedby a spring abutment 26, so as to permit a slight axial movement of thegear 25 in one direction upon its shaft 24. In the form shown in Fig. 1,the abutment 26 is placed beyond gear 25 and held in position by collar27, whereas in the form shown in Fig. 2, the abutment is placed betweenthe gear 25 and the casing of the motor 10.

Arranged parallel with shaft 24 1s a stud 29 upon which is journaled aspiral gear 30 which meshes with ear 25, said gear being freelyrotatable and axially movable upon stud 29, the axial movementbeinglimited in one direction by the motor casing, and in the otherdirection by collar 31. The spiral gear 30 carries a spur pinion 32which is capable of meshing with gear 33, carried by, or connected to,the motor which is to be started, said gear conveniently being carr1edby, or formed upon, fiy wheel 34 of the motor to be started.

The direction of pitch of the spiral teeth of gear 25 depends upon thedirection in which the gear 32 is to be shifted axially in order to bebrought into mesh with gear 33, as indicated in Figs. 1 and 2, and theabutment 26 is so placed that, when gear 32 meets the resistance of gea33, gear 25 may have a slight axial yielding upon its shaft, therebyavoiding the shock which would otherwise occur.

In operation, a depression of the pedal 22 forces switch 18 into contactwith terminal 17 thus completing the battery circuit and setting themotor 10 into operation, rotating shaft 24 in the direction indicated bythe arrows in Figs. 2 and 3. The slight resistance offered by gear 30 torotation under a driving force applied by gear 25, causes the gear 30 toshift axially upon stud 29 and to drive gear 32 into engagement withgear 33. The meshing of gear 32 with gear 33 places the motor under thesudden load of the gear 33 and its connected parts so that if the gear25 were axially unyielding, the starting motor would be jarred. Theabutment spring 26, however, permits the gear 25 to momentarily shiftaxially so as to avoid this jarring, and, as the gear 33 acquiresvelocity under the driving effect of the motor 10, spring 26 will returnthe gear 25 to its initial position. As soon as the started motor isdriven under its own power, the speed of gear 33 will be considerably inexcess of the speed of gear 32 under the driving force of motor 10 andconsequently, because of the interaction of the two-spiral gears 25 and30, the gears 30 and 32 will be shifted axially so as to cause gear 32to be withdrawn from gear 33. As soon as the started motor has begun tooperate under its own power, the operator will release switch 18 so thatspring 21 may swing it into contact with terminal 16, thus cutting outthe motive current or motor 10, and at the same time closing thearmature circuit through the resistance circuit 15, so as to cause asudden stoppage of the shaft 24, this sudden stoppage materiallyassisting in the automatic wlthdrawal of gear 32 from gear 33.

I am aware that starting devices embodying an axially shiftable gearshifted by the coaction of threaded parts have been commonly in use, butin practice it is found that if these threaded parts are a sufiicientlytight fit to prevent accidental meshing with the gears, then theunavoidable accumulation of dirt upon the threaded members oftenprevents the shifting operation, because the axial shifting is entirelydependent upon the inertia of the shifting element. In my presentconstruction, gears 25 and 30 may very closely and accurately fit eachother and the bore of gear 30 may closely fit pin 29, so that anyaccumulation of dirt upon the exposed portion of pm 29 w 1ll not in anyway prevent the posltive shiftlng of the gear 32 into, or out of, meshwlth gear 33.

In view of the fact that stud 30 has no rotative movement, it will beapparent that any condition of this stud, which offers an increasedresistance to the rotative movement of gear 30 will act merely to insurethe projection of this gear axially on the stud, because no materialrotative force can be transmitted through gear 30 until its axialmovement is positively arrested after pinion'32 has been brought intomesh with gear 33.

I claim as my invention:

1. A motor starting apparatus comprising two meshing spiral gears, oneto be driven by the starting motor and capable of limited axial movementagainst the action of a yielding abutment and the other to be connectedto the motor to be started, the said yielding abutment, a spur gearcarried by the other of the spiral gears, a support for said otherspiral gear and the associated spur gear, said support permitting bothrotative and axial movement of the connected spiral and spur gears, saidaxial movement from normal being in the direction of ac-' tion of thesprin abutment.

2. A starting evice comprising an electric motor, a spiral gear drivenby said motor and capable of limited axial movement,

a yielding abutment opposing said axial movement, a second spiral gearmeshing with the first-mentioned spiral gear, and mounted for axialmovement, means to limit said axial movement, a spur gear carried bysaid second spiral gear, controlling circuits for said motor comprisingan energizing circuit and a braking circuit and a switch for alternatelopening and closing said energizing circult and braking circuit.

3. A starting device comprising an electric motor, a spiral gear drivenby said motor, a second spiral gear meshing with the first mentionedspiral gear, and mounted for axial movement, means to limit said axialmovement, a spur gear carried by said second spiral gear, controllingcircuits for said motor comprising an energizing circuit and a brakingcircuit, and a switch for alternately opening and closing saidenergizing circuit and braking circuit.

4. A starting device comprising an electric motor, a rotativetransmitting element automatically shiftable into effective position bymovement of the motor under its own power, and shiftable to ineffectiveposition by the application of an external driving force at a hi hervelocity, an energizing circuit for sai motor, a braking circuit forsaid motor, and a switch for alternately opening and closing saidenergizing circuit and braking circuit.

5. The combination with an internal combustion engine I provided with arotative member to which an external driving force may be applied, anelectric starting motor, a rotative transmitting element automaticallyshiftable into effective engagement with the rotative element of theinternal combustion motor by movement of the electric motor under itsown power, and shiftable to ineffective position by the driving forceapplied by the internal combustion engine at a higher velocity, anenergizing circuit for said electric motor, a braking circuit for saidelectric motor, and a switch for alternately opening and closing saidenergizing circuit and brakin circuit.

In witness whereof, I have hereunto set my hand at Indianapolis,Indiana, this tenth day of February, A. D. one thousand nine hundred andseventeen.

DALMAR T. BROWNLEE.

